CMOS (Complementary Metal-Oxide Semiconductor) image sensors may exemplify solid-state imaging devices installed in digital video cameras, digital still cameras, smartphones, mobile phones, etc. In CMOS image sensors, photoelectric charges are accumulated in pn junction capacitance of photodiodes that serve as photoelectric conversion elements; the photoelectric charges thus accumulated are read out through MOS transistors.
Existing solid-state imaging units generally use a pixel array in which red, green, and blue pixels are arranged on a plane, which causes a false color associated with generation of a color signal by execution of interpolation between pixels. Hence, a study has been made of a longitudinal spectroscopic type solid-state imaging device in which red, green, and blue photoelectric conversion regions are stacked along a longitudinal direction of a same pixel. For example, in Patent Literature 1, there is disclosed a solid-state imaging device in which photodiodes of blue and red are stacked in a semiconductor substrate and a green photoelectric conversion element using an organic photoelectric conversion film is provided on light receiving surface side (rear surface side or first surface side) of the semiconductor substrate.